Back flow limiting device for failed redundant parallel fan

Abstract

A plurality of parallel fans are mounted for moving side-by-side columns of air in a chassis. A louver member is provided adjacent each fan. Each louver member is bendable from a closed position to an open position by a flow of air generated by its respective fan, and is restrictedly bendable to a closed position, in engagement with a portion of an air passageway, in response to failure of its respective fan.

What is claimed is: 
     
       1. A flow limiting apparatus for a failed fan comprising: a plurality of parallel fans mounted for moving side-by-side columns of air in a chassis;   a frame mounted adjacent each fan, the frame including a plurality of side-by-side openings formed therein, each opening aligned with a respective fan and including a center mount supported therein by the frame; and   a plurality of louver members, one louver member mounted adjacent each opening, each louver member including a hub and a plurality of flexible flaps each including a narrow portion and extending radially from the hub, each hub being attached directly to the center mount of its respective opening, whereby each flap is bendable at the narrow portion in a first direction to overlap with each adjacent flap due to a flow of air generated by its respective fan, and limited for partial movement in a second direction, opposite the first direction, in response to failure of its respective fan.   
     
     
       2. The apparatus as defined in claim 1 wherein each hub is adhered to its respective center mount. 
     
     
       3. The apparatus as defined in claim 1 wherein movement of each louver member in the second direction is limited by the frame of its respective opening, whereby the louver member blocks air flow therethrough. 
     
     
       4. The apparatus of claim 2 wherein each flap is flexible for permitting bending adjacent the hub in response to air flow thereacross. 
     
     
       5. A computer system comprising: a chassis having a first portion and a second portion therein;   a plurality of parallel fans mounted for moving side-by-side columns of air in the chassis from the first portion to the second portion;   a frame mounted adjacent each fan, the frame including a plurality of side-by-side openings formed therein, each opening aligned with a respective fan and including a center mount attached to the frame; and   a plurality of louver members, one louver member mounted adjacent each opening, each louver member including a hub and a plurality of flexible flaps each including a narrow portion and extending radially from the hub, each hub being attached directly to the center mount of its respective opening, whereby each flap is bendable at the narrow portion from a closed position to an open position to overlap with each adjacent flap due to a flow of air generated by its respective fan, and bendable to the closed position in response to failure of its respective fan.   
     
     
       6. The system as defined in claim 5 wherein each hub is adhered to its respective center mount. 
     
     
       7. The system as defined in claim 6 wherein each flap is bendable adjacent the hub. 
     
     
       8. The system as defined in claim 5 wherein movement of each louver member to the closed position is limited by a frame of its respective opening, whereby the louver member blocks air flow therethrough. 
     
     
       9. A computer system comprising: a chassis;   at least one microprocessor mounted in the chassis;   at least one input coupled to provide input to the microprocessor;   a least one storage coupled to the microprocessor;   at least one display coupled to the microprocessor by a video controller;   at least one memory coupled to provide storage to facilitate execution of computer programs by the microprocessor;   a plurality of parallel fans mounted for moving side-by-side columns of air in the chassis;   a frame mounted adjacent each fan, the frame including a plurality of side-by-side openings formed therein, each opening aligned with a respective fan and including a center mount supported therein by a plurality of ribs; and   a plurality of louver members, one louver member mounted adjacent each openings, each louver member including a hub and a plurality of flexible flaps each including a narrow portion and extending radially from the hub, each hub being attached directly to the center mount of its respective opening, whereby each flap is bendable at the narrow portion from a closed position to an open position to overlap with each adjacent flap due to a flow of air generated by its respective fan, and bendable to the closed position in response to failure of its respective fan.   
     
     
       10. The system as defined in claim 9 wherein each hub is adhered to its respective center mount. 
     
     
       11. The system as defined in claim 7 wherein each flap is bendable adjacent the hub. 
     
     
       12. The system as defined in claim 9 wherein movement of each louver member to the closed position bends the flaps into engagement with the frame portion defining the opening. 
     
     
       13. A method of cooling comprising the steps of: mounting a plurality of fans in a chassis for moving side-by-side columns of air;   forming louver members to each include a plurality of deformable flaps each flap having a narrow portion and extending radially from a hub;   forming a frame including a plurality of side-by-side openings therein, each opening including a center mount supported therein by the frame;   mounting the frame in the chassis adjacent the fans so that each opening is aligned with a respective fan;   mounting a louver member in each opening adjacent each fan so that each hub is attached directly to a respective center mount for movement of the flaps between an open position and a closed position;   deforming the flaps at the narrow portion of the louver member to the open position to overlap with each adjacent flap in response to operation of its respective fan; and   restrictive flexing the flaps of the louver member to the closed position into engagement with a portion of the opening in response to failure of its respective fan.   
     
     
       14. A flow limiting apparatus comprising: a frame including a plurality of side-by-side openings formed therein, each opening including a peripheral edge, and a center mount supported therein by a plurality of ribs;   a flexible louver member mounted adjacent each opening, each louver member including a hub and a plurality of flexible flaps each including a narrow portion and extending radially to a peripheral portion distal from the hub, each hub being attached directly to the center mount of its respective opening; and   the peripheral portion of each flap being movable to overlap with each adjacent flap in response to fan generated air flowing across the louver member.   
     
     
       15. The apparatus as defined in claim 14 wherein the flaps are bendable adjacent the hub. 
     
     
       16. The apparatus as defined in claim 14 wherein the flaps are formed by cuts in the flexible member.